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Denafrips ARES II USB R2R DAC Review

Shoaibexpert

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Let's call this DAC audibly transparent in OS mode.
Curious to see if Denafrips at least solved the treble roll-off in lower bitrates in NOS and how the slow filter in OS performs.
Those wanting to spend considerably less on a DAC with similar performance (or better) have plenty to choose from but you can do much less for a lot more money as well.
Thats true...
 
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Since this is called audio science review it is amusing to see how many unscientific comments are being made about delta sigma and r2r dacs being the same. Here is a link to a presentation by no other than Burr Brown stating clearly that R2R is superior but more expensive. The only reason for the existence of delta sigma is cost reduction.

http://www.jitter.de/pdfextern/DesignSem5.pdf
 

majingotan

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Since this is called audio science review it is amusing to see how many unscientific comments are being made about delta sigma and r2r dacs being the same. Here is a link to a presentation by no other than Burr Brown stating clearly that R2R is superior but more expensive. The only reason for the existence of delta sigma is cost reduction.

http://www.jitter.de/pdfextern/DesignSem5.pdf
Your ppt slides is quite obsolete BTW. Have you explored enough measurements on this site before making inaccurate statements?
 

BDWoody

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Since this is called audio science review it is amusing to see how many unscientific comments are being made about delta sigma and r2r dacs being the same.
Ummm...who said they were the same? They clearly have different basic architecture...

A very good one is likely indistinguishable from most any competent D/S under any kind of controlled listening. Is that what you are taking issue with?

Also, first post seems a bit on the needlessly provocative side... Do we have a newly minted troll?
 
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I should have explained myself better.
There are many comments like "R2R can measure quite well too", "Not bad for R2R" or "I fail to understand the appeal of R2R" implying that DS is superior or R2R is at best the same as DS.

I see no mention of the difference between R2R DAC chips with laser trimmed resistors and R2R using discrete resistor ladders where 0.1% tolerance is clearly insufficient.

Indeed the two function in a fundamentally different way.

A DS dac with only a few bits needs loads of signal processing and feedback to increase the apparent resolution. The resolution of a ladder DAC is intrinsic to its design and does need correction.

Of course both can sound good or bad.
 

Veri

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A DS dac with only a few bits needs loads of signal processing and feedback to increase the apparent resolution. The resolution of a ladder DAC is intrinsic to its design and does need correction.
You realise any R2R DAC performing at 'modern' D-S performance levels, reaches it only via lots and lots of FPGA-programmed feedback, to offset the resistor errors throughout the conversion?

Correction, feedback, in any case you'd want the cleanest output..
 

YSC

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I should have explained myself better.
There are many comments like "R2R can measure quite well too", "Not bad for R2R" or "I fail to understand the appeal of R2R" implying that DS is superior or R2R is at best the same as DS.

I see no mention of the difference between R2R DAC chips with laser trimmed resistors and R2R using discrete resistor ladders where 0.1% tolerance is clearly insufficient.

Indeed the two function in a fundamentally different way.

A DS dac with only a few bits needs loads of signal processing and feedback to increase the apparent resolution. The resolution of a ladder DAC is intrinsic to its design and does need correction.

Of course both can sound good or bad.
But unless it’s a NOS r2r, those sample processes of oversampling are applied to both DS and R2R, nothing really pure as you’ve stated
 

BDWoody

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I should have explained myself better.
There are many comments like "R2R can measure quite well too", "Not bad for R2R" or "I fail to understand the appeal of R2R" implying that DS is superior or R2R is at best the same as DS.
They typically haven't had very good execution...leading to very poor measured results.

Since the job of the DAC is to be transparent, and the rest is details, I am one of those who wonders what people are expecting when they buy one of these. It doesn't bother me...i just wonder what made them believe it should be 'better' somehow.

It isn't about sounding good or bad... it's unlikely anyone on the planet could distinguish one from the other (assuming they are both well executed designs) under controlled conditions.
 
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"You realise any R2R DAC performing at 'modern' D-S performance levels, reaches it only via lots and lots of FPGA-programmed feedback, to offset the resistor errors throughout the conversion?"

Where does a resistor ladder consign only of resistors and switches have signal processing or feedback? Please explain.

Oversampling (bad name as it is simply a digital low pass filter) is of course a form of signal processing but that's independent of the type of DAC chip. We are comparing DS with R2R these are converters. Oversampling is another matter.
 

BDWoody

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"They typically haven't had very good execution...leading to very poor measured results."

So a PCM1704 has poor measured results?!?
Not sure how you made that leap, from me saying they typically haven't had good measured results, to you pulling out the exclamation points...but a quick search on this site will show some that have been tested, and typically it's just been sad.

Rather than start from scratch, in an off topic thread...maybe this would give more background on the general thinking.

https://www.audiosciencereview.com/...sigma-vs-“multibit”-what’s-the-big-deal.5359/
 

solderdude

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So a PCM1704 has poor measured results?!?
PCM1704 is not a 'typical' R2R based chip (it is sign magnitude) and a 20 year old chip. While it has very good results measurement wise it isn't quite reaching the level of the better DS applications.

Of course the final DAC device results not only depend on the used DAC chip but also how it used and what components/layout is used around the DAC chips and what the DAC chip is told to 'do'.
 
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"'modern' D-S performance levels"

which are what?

Lets say 8 bit delta sigma?

The resistor ladder in these has a native resolution of 256 possible values or steps. The rest is apparent resolution through the use of signal processing and feedback.

A 24 bit ladder has a native resolution of 24 bit (proving the resistors can be trimmed precisely enough). No feedback or signal processing is present.

What is so difficult to understand?
 
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"Whatever performance level is desired, a sigma-delta DAC can achieve it cheaper than an R-2R design. Either type can be made terrible, excellent, or somewhere in between."

Exactly what I intended with my original post. DS is cheaper. Not "better" as was implicated throughout the thread.
I am unaware of pricing but apparently a top notch DS like ESS sabre is apparently not exactly cheap.
 

BDWoody

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What is so difficult to understand?
I'm having a hard time understanding your point...

What am I missing.
It's harder to get r2r right, and there's no audible advantage over a $9 apple dongle.
 

mansr

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A 24 bit ladder has a native resolution of 24 bit (proving the resistors can be trimmed precisely enough). No feedback or signal processing is present.
That's where you're mistaken. Resistor trimming alone can only take you so far. You then have to account for the remaining mismatch, drift, temperature gradients, etc. A couple of designs have managed to achieve very low distortion figures through (presumably individual) calibration and digital compensation. This takes a huge amount of engineering effort, and the resulting product is very expensive to make. Why do things the hard way?

Exactly what I intended with my original post. DS is cheaper. Not "better" as was implicated throughout the thread.
I am unaware of pricing but apparently a top notch DS like ESS sabre is apparently not exactly cheap.
Same performance cheaper is a very reasonable definition of better. The ES9038PRO costs $75 for samples which means it can probably be had for about $35 in 1k quantities. The Moolah-Moolah DAC has three ADI Sharc DSPs that cost about $20 each plus a bunch of other expensive parts.
 
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"A couple of designs have managed to achieve very low distortion figures through (presumably individual) calibration and digital compensation."

Interesting. Which designs are that?

I understand the pcm1704 was the last R2R chip manufactured. There is no mention of digital signal processing in the datasheet.
 

solderdude

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The resistor ladder in these has a native resolution of 256 possible values or steps. The rest is apparent resolution through the use of signal processing and feedback.
You (conveniently) left out the important parts of the DS design.
The high frequency it operates on as opposed to the lower frequency of the R2R and the low pass filter.
 
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